EP3354345B1 - Grinding screen for a device for grinding bulk material - Google Patents

Description

The invention relates to a shredding sieve according to the preamble of claim 1 for a device for shredding piece goods, which has a housing with at least a first housing part and a second housing part and a rotor on which tools for shredding the piece goods are attached. The shredded piece goods can get out of an effective area of the rotor via the shredding sieve.

Such a crushing sieve is, for example, from DE 472 243 C known. This document describes a beater or hammer mill whose grinding path can be moved out of the housing through a door. In order to avoid contact between the grinding track and the rotor, part of the grinding track can be lowered by actuating a screw spindle. Devices for shredding piece goods are used in a variety of ways. In many branches of industry, for example in the chipboard industry, in the production of pellets and briquettes or in the production of biomass, it is necessary to shred piece goods, in particular wood. The material to be crushed can, for. B. consist of waste wood, planing, milling or sawdust, coarse classifier or green waste. So-called hammer mills or hammer crushers are usually used for this purpose. These mostly have a drum-shaped housing in which a rotor is arranged, over the outer surface of which tools for comminuting the piece goods are distributed. These tools can be breaking tools, for example hammers, or cutting tools, for example knives. The rotor is in operation of the Device set in rotation so that the tools come into contact with the piece goods to be shredded. This piece of cargo is shredded by the tools.

The comminuted piece goods usually leave the area of action of the rotor through the comminuting sieve, which can also be a perforated disk or the like, for example. The piece goods then move through a discharge shaft in order to be transported away afterwards.

The area of action of the rotor is defined as the spatial area in which the shredding tools move. The effective area is therefore generally cylindrical and has a radius that corresponds to the sum of the rotor radius and the tool length. In this area the tools unfold their effect and can shred the piece goods to be shredded.

In the present case, a shredding sieve is understood to mean any device by means of which it can be achieved that components of the shredded piece goods whose size exceeds a maximum size are held inside the housing, while components of the shredded piece goods whose size is below the maximum size can leave the device .

Both the crushing tools and the crushing sieves are subject to constant wear. As a result, they have to be replaced or serviced regularly. In addition, it is possible that the crushing sieve used should be exchanged for another one, since, for example, the crushed piece goods should have a different size distribution.

It is known from the prior art to provide one or more doors or comparable openings on one side of a hammer mill, through which access to the outer surface of the rotor and to the comminuting tools attached to the rotor is achieved. Maintenance and repair work can be carried out through this opening. However, it must After opening the doors, the shredding screen can also be removed to gain access to the rotor and the tools attached to it. This is usually complex and time-consuming, since the comminuting sieve is often connected to the housing of the hammer mill with a large number of screws.

the JP 2011 251216 A is provided for this purpose with a two-part sieve which is arranged below the rotor and which is arched and screwed to the housing via a portafilter. If the screw connection is loosened, the two portafilter fold apart and pivot down into the housing. They can be pushed out together via doors provided in the housing.

the DE 40 08 276 A1 discloses a hammer mill with a radially adjustable sieve shell for comminuting grains, long or pre-chopped roughage and other agricultural and food products, in which the sieve shell forming the grinding chamber encloses the rotor and consists of two halves which are individually rotatably mounted in radially adjustable sieve holders . When the lower sieve holder, which consists of an assembly, moves in the direction of the center of the rotor, the halves of the sieve are inevitably moved in the direction of the impact circle of the beaters.

the DE 19713264 C1 describes a hammer mill with two rotors rotating in opposite directions and multi-part breaking tracks that can be pulled out from the side. Part of the grinding track is designed to be pivotable and can be brought into a working position by being pushed into the housing.

the CA 2429244 describes a comminuting device which has a housing part which can be displaced linearly together with a part of the comminuting sieve so that the rotor is accessible.

The invention has for its object to provide a crushing sieve according to the To improve the preamble of claim 1 so that maintenance and repair of the device or replacement of the shredding sieve or parts of the device is possible simply, quickly and safely for those involved.

The invention solves the problem posed by a comminuting sieve according to claim 1. The comminuting sieve has a pivoting part which is mounted pivotably about a pivot axis and which can be pivoted into a holding position in that the first housing part and the sliding part of the comminuting sieve are brought into the maintenance position, the pivoting part forms a walk-on work platform in the holding position. The device for comminuting piece goods has a discharge shaft for comminuted piece goods and the pivoting portion of the shredding sieve spans the discharge shaft at least partially in the holding position. With this configuration, the rotor can be exposed in a single operation and access to both the rotor and the tools can be achieved. In addition, the shredding sieve is accessible so that cleaning, maintenance, repair or replacement work can be carried out easily. The shredding sieve can remain in the assembled state, which significantly reduces the time required and the workload. Of course, it is sufficient if part of the rotor, for example part of its outer surface, is made accessible. The rotor is rotatably mounted so that the entire surface area is accessible by turning the rotor. Accessible means that the necessary cleaning, maintenance or repairs are possible.

The first housing part can be displaced relative to the second housing part, for example, via a hydraulic system or a spindle drive. Of course, other types of drive are also conceivable.

The comminuting sieve has a pivoting part which is mounted pivotably about a pivot axis and which can pivot into a holding position is in that the first housing part and the sliding part of the shredding sieve are brought into the maintenance position, the pivoting part in the holding position forming a work platform that can be walked on.

As already stated, in such devices the housing and the rotor are mostly drum-shaped or cylindrical. This cylinder usually has an extension running in the axial direction that is too large to be able to carry out maintenance and repair work over the entire cylinder surface of the respective rotor or of the shredding sieve by simply reaching into it. It is therefore imperative for a person who is to carry out the corresponding work to climb into the device. In this case, however, as a rule, no separate work platform is provided in these devices, since the distance between the tools located on the rotor and the comminuting sieve should be kept as small as possible when the device is in operation. There is no structural space for a separate work platform, which enables comfortable work during maintenance or cleaning work.

However, the design described here ensures that part of the comminuting sieve, namely the pivoting part, forms a work platform and thus enables particularly convenient and safe work inside the device.

Advantageously, the sliding part and the pivoting part of the comminuting sieve are releasably connected to one another by at least one locking bolt. This connection is particularly advantageously achieved by two locking bolts. In this way, a pivotable connection between the sliding part and the pivoting part of the comminuting sieve is achieved in a particularly simple manner and, in addition, this connection is easy to detach. If, for example, a used crushing sieve is to be exchanged for another comminuting sieve that has, for example, a different mesh size, the The swivel part of the respective shredding sieve can be easily removed by loosening the locking bolts and exchanged for the swiveling part of the other shredding sieve.

The device advantageously has a discharge chute for shredded piece goods, the pivoting portion of the shredding sieve in the holding position at least partially spanning this discharge chute. Conventionally, the piece goods to be comminuted are introduced into the device from above. The shredded piece goods leave the device mostly downwards following the force of gravity. The discharge chute is consequently arranged at this point, through which the shredded piece goods fall and are then transported away, for example, with a chain conveyor, a conveyor belt, a double screw conveyor or other conveyors. A connecting shaft, the so-called discharge shaft, is therefore installed at the outlet of the device, which can be a hammer mill, for example.

When the machine housing is raised or opened, i.e. in the state in which the first housing part is in the maintenance position and thus at least part of the rotor is accessible, there is a risk that people who work inside the device will fall through the discharge shaft and get injured in this way. In the present case, however, the pivoting part is pivoted into the holding position when the first housing part is brought from the working position into the maintenance position. The pivoting part not only forms the work platform that can be walked on, but advantageously also covers at least part of this discharge shaft and thus also increases work safety. Advantageously, the pivoting portion of the shredding sieve makes up approximately one third of the total shredding sieve. This makes it possible, advantageously, to span the discharge shaft completely.

It has been found to be advantageous if a portafilter is arranged on the first housing part and a counter-screen carrier is arranged on the second housing part in such a way that the comminuting sieve between the portafilter and the Counter-sieve carrier can be clamped in that the first housing part is brought from the maintenance position into the working position. By moving the first housing part and the second housing part together relative to one another it is consequently achieved that the comminuting sieve is clamped between the sieve holder and the counter-sieve holder, which are arranged on the different housing parts. Complicated and time-consuming fastening of the comminuting sieve to the respective portafilter, for example by means of a large number of screws or similar connecting elements, is therefore not necessary. In this way, it is quick and easy to exchange a shredding sieve for another shredding sieve.

Since the number of elements that can be lost, for example screws or bolts, is greatly reduced in this way, the risk of inadequately fastened comminuting sieves is also reduced. In this embodiment, there is no longer any possibility of insufficiently fastening the comminuting sieve, for example with an insufficient number of screws, on the respective portafilter. As soon as the first housing part and the second housing part are moved towards each other and the first housing part is in the working position, it is ensured at the same time that the comminuting sieve is properly secured in the desired and intended position. This also increases work safety and greatly reduces the risk of accidents.

In an advantageous embodiment, the pivoting part of the comminuting sieve, which is particularly detachably fastened, is designed in the form of a grinding track, for example a comminuting grinding track or a rasping track. The simple releasability of the pivoting part on the sliding part of the shredding sieve makes it particularly easy to replace it, so that the respective requirements for the piece goods to be shredded can be taken into account quickly and easily.

The swivel portion of the shredding sieve is out of the holding position pivotable into a sieve position by bringing the first housing part out of the maintenance position into the working position. Since the pivoting part forms the accessible work platform in the holding position, it is consequently not necessary to bring the pivoting part into the sieve position, for example by hand or by actuating an actuator, in which the pivoting part of the shredding sieve acts as a comminuting sieve part. Rather, this is already achieved in that the first housing part is brought from the maintenance position into the working position. It is consequently impossible, for example, after maintenance or repair work has been completed, to forget to bring the pivoting part from the holding position into the sieving position before the first housing part is brought from the maintenance position into the working position. Such a separate work step is not necessary.

A projection is arranged on the pivot part 2, which slides along a guide arranged on the second housing part and thus ensures pivoting of the pivot part when the first housing part is displaced relative to the second housing part. The projection can also be designed, for example, as a roller or wheel that rolls on the guide. In this way, both when moving the two housing parts apart from the working position to the maintenance position and in the opposite direction, it is ensured that a smooth and flowing movement of the swivel part is achieved and wedging, falling or tilting of the swivel part can be almost reliably ruled out. If the pivoting part of one comminuting sieve is replaced by the pivoting part of another comminuting sieve, only the projection has to be placed on the guide provided for it. No further adjustment or alignment of the components relative to one another is necessary.

The comminuting sieve preferably has a partially cylindrical shape with a sieve radius, and the portafilter and the counter-sieve holder are designed to accommodate different comminuting sieves which have sieve radii different from one another. For this purpose, for example, in the machine housing the sieve supports are screwed in, whereby different sieve radii can be realized by, for example, different spacer inserts in the device and the corresponding sieve supports can be changed very quickly. This is necessary, for example, in order to adapt the sieve spacings from the striking or cutting tool, which is arranged on the respective rotor, to the comminuting sieve, if, for example, another, for example shorter or longer, tool is arranged on the rotor. For this purpose, adjustable sieve hold-downs, which can be part of the portafilter and the counter-sieve carrier, for example, are adjusted to a new dimension. Then another comminuting sieve with a, for example, larger or smaller sieve radius can be inserted and used. This means that the screen distance from the striking or cutting tool to the shredding screen can be adapted and individually set. The crushing sieve is again clamped in that, after the crushing sieve has been inserted into the portafilter, the two machine bodies are moved towards each other, for example by hydraulics or mechanics, so that the first housing part is moved from the maintenance position to the working position. In this way alone, the shredding sieve is clamped between the portafilter and the counter-sieve carrier and secured in the machine.

The portafilter and the counter-screen carrier are therefore preferably designed to be adaptable to different screen radii.

The comminuting sieve is preferably attached to the portafilter by at least one quick-release bolt. This achieves an even more secure attachment of the shredding sieve to the portafilter, so that the shredding sieve on the portafilter is prevented from slipping on the portafilter, especially when the two housing parts move together while the first housing part is being moved from the maintenance position to the working position.

Figur 1 -

eine Vorrichtung gemäß einem ersten Ausführungsbeispiel in der Arbeitsposition in einer Seitenansicht,

Figur 2 -

eine Detailansicht unterschiedlicher Bauteile einer Vorrichtung gemäß einem Ausführungsbeispiel der vorliegenden Erfindung,

Figur 3 -

eine Vorrichtung gemäß einem Ausführungsbeispiel der vorliegenden Erfindung in der Arbeitsposition und

Figur 4 -

die Vorrichtung aus Figur 3 in der Wartungsposition.

An exemplary embodiment of the present invention is explained in more detail below with reference to a drawing. It shows:

Figure 1 -

a device according to a first embodiment in the working position in a side view,

Figure 2 -

a detailed view of different components of a device according to an embodiment of the present invention,

Figure 3 -

a device according to an embodiment of the present invention in the working position and

Figure 4 -

the device off Figure 3 in the maintenance position.

Figure 1 shows in the upper area a side view of a device 2 according to a first embodiment of the present invention. The device 2 has a first housing part 4 and a second housing part 8, which are shown enlarged in the lower area. A rotor 6 is located between the two housing parts 4, 8.

In the lower left area, the first housing part 4 is shown enlarged. One recognizes a portafilter 10 on which a displacement part 12 of a comminuting sieve, shown to the right, is arranged. The displacement part 12 has a partially cylindrical contour and, in particular, has a sieve radius on the inside.

On the area of the first housing part 4 opposite the portafilter 10, a door 24 is shown, which is arranged on the first housing part 4 via hinges 22 and can be opened using a handle 26. In this way, access is possible, for example, to a rear side of the sliding part 12 of the comminuting sieve.

Figure 1 also shows a pivoting part 14, which via locking bolts 16 is attached to the sliding part 12. For this purpose, the locking bolts 16 are guided through receptacles 18 on the pivot part 14 and through receptacles 20 on the displacement part 12 and thus connect the two components 12, 14 to one another. The sliding part 12 and the pivoting part 14 together form the shredding sieve. The pivot portion 14 is shown in two different positions. The pivoting part 14 is shown in the holding position in somewhat thicker lines, in which a surface 34 can be walked on and serves as a work platform. The pivoting component 14 is shown in the sieve position in somewhat thinner lines and pivoted about the receptacles 18.

In the lower right area of the pivoting part 14, a projection 36 is shown, which in the assembled state slides along a guide 38 when the first housing part 4 and thus also the shredding sieve attached to it is brought from the working to the maintenance position or vice versa. As the projection 36 slides on the guide 38, the pivot portion 14 is pivoted about the pivot axis which is formed by the receptacles 18, 20 and the locking bolts 16. If the first housing part 4 is in the working position, the projection 36 engages in an undercut 40 provided for this purpose.

Figure 2 shows an enlarged representation of some of the components already mentioned.

In the lower right area, the first housing part 4 with the portafilter 10, the sliding part 12 and the pivoting part 14 is shown again. It can be seen that the pivoting part 14 also has a sieve radius, but does not continue the sieve radius of the displacement part 12 in the position shown. The pivoting part 14 is consequently in the holding position.

To the left of this is a front view of the shredding sieve, the individual holes 28 of the sieve being shown. The shredding sieve and in particular the one in the lower left area of the Figure 2 shown The sliding part 12 of the shredding sieve is fastened to the portafilter 10 via quick-release bolts 30. This is in the upper left area of the Figure 2 shown enlarged. The quick release bolts 30 can be seen, which are shown in the upper left area once in the non-connected and once in the connected state. The quick release bolt 30 connects the sliding part 12 of the shredding sieve to the portafilter 10. A safety clip 32 is provided to prevent the bolt from being pulled out. Also in the upper right area of the Figure 2 a quick release bolt 30 is shown.

Figure 3 shows the device 2 in the closed state. In the right area of the device 2 there is a drive device 42, by means of which the rotor 6 can be set in rotation. It can be seen that the first housing part 4 and the second housing part 8 are in direct contact with one another, so that the first housing part 4 is in the working position. Both the sliding part 12 and the pivoting part 14, which together form the shredding sieve, are shown as dark elements. On the right-hand part of the pivoting part 14, the projection 36, which has engaged in the undercut 40, can be seen.

A hydraulic piston 44 is shown below the rotor 6, which in FIG Figure 3 shown condition has its minimum length. The first housing part 4 can be displaced relative to the second housing part 8 via a rail system 46 as soon as the hydraulic piston 44 moves the two components 4, 8 away from one another. In particular, the displacement part 12 is between the portafilter 10 and the, for example, in Figure 1 shown Gegenensiebträger 48 clamped.

Figure 4 shows the device 2 from Figure 3 when open. It can be seen that the first housing part 4 has been displaced along the rail system 46 relative to the second housing part 8 and the rotor 6. The pivoting part 14 of the shredding sieve is now in the holding position and can be used as a work platform. The protrusion 36 is along has slid off the guide 38 and has ensured that the pivoting part 14 is pivoted relative to the sliding part 12.

List of reference symbols

2

contraption

4th

first housing part

6th

rotor

8th

second housing part

10

Portafilter

12th

Shift share

14th

Swivel portion

16

Locking bolt

18th

admission

20th

admission

22nd

hinge

24

door

26th

Handle

28

Holes

30th

Quick release bolts

32

Safety clip

34

surface

36

head Start

38

guide

40

Undercut

42

Drive device

44

Hydraulic piston

46

Rail system

48

Counter screen carrier

Claims (5)

1. A comminution filter adjusted to be used in a device comprising a first housing part (4) and a second housing part (8) for comminuting bulk goods, with a displacement element (12) featuring holes (28) and a swivel element (14) that can be swivelled from a filter position into a holding position, characterised in that the swivel element (14) comprises a surface (34) that can be accessed in the holding position and used as a working platform; the swivel element (14) swivels into the holding position by displacing the displacement element (12) from a working position into a maintenance position; and the swivel element (14) features a projection (36) that can slide along a guide (38) configured on the second housing part (8) when said element is swivelled from the filter position into the holding position.
2. The comminution filter according to claim 1, characterised in that the displacement element (12) and the swivel element (14) are detachably connected to one another by at least one locking bolt (16).
3. The comminution filter according to claim 1 or 2, characterised in that the projection (36) slides along the guide (38) arranged on the second housing part (8), thereby ensuring a swivelling of the swivel element (14) when the first housing part (4) is displaced relative to the second housing part (8).
4. The comminution filter according to one of the preceding claims, characterised by a partially cylindrical form with a filter radius.
5. The comminution filter according to one of the preceding claims, characterised in that it is fixed by at least one quick-clamping bolt (30) to a filter holder (10) arranged on the first housing part.

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